/*
 * Copyright (c) 2007, 2015, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 2000-2002,2004 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.sun.org.apache.xerces.internal.xni;

import com.sun.org.apache.xerces.internal.xni.parser.XMLDTDContentModelSource;

/**
 * The DTD content model handler interface defines callback methods
 * to report information items in DTD content models of an element
 * declaration. Parser components interested in DTD content model
 * information implement this interface and are registered as the DTD
 * content model handler on the DTD content model source.
 *
 * @author Andy Clark, IBM
 * @see XMLDTDHandler
 */
public interface XMLDTDContentModelHandler {

  //
  // Constants
  //

  // separators

  /**
   * A choice separator for children and mixed content models. This
   * separator is used to specify that the allowed child is one of a
   * collection.
   * <p>
   * For example:
   * <pre>
   * &lt;!ELEMENT elem (foo|bar)&gt;
   * &lt;!ELEMENT elem (foo|bar+)&gt;
   * &lt;!ELEMENT elem (foo|bar|baz)&gt;
   * &lt;!ELEMENT elem (#PCDATA|foo|bar)*&gt;
   * </pre>
   *
   * @see #SEPARATOR_SEQUENCE
   */
  public static final short SEPARATOR_CHOICE = 0;

  /**
   * A sequence separator for children content models. This separator
   * is used to specify that the allowed children must follow in the
   * specified sequence.
   * <p>
   * <pre>
   * &lt;!ELEMENT elem (foo,bar)&gt;
   * &lt;!ELEMENT elem (foo,bar*)&gt;
   * &lt;!ELEMENT elem (foo,bar,baz)&gt;
   * </pre>
   *
   * @see #SEPARATOR_CHOICE
   */
  public static final short SEPARATOR_SEQUENCE = 1;

  // occurrence counts

  /**
   * This occurrence count limits the element, choice, or sequence in a
   * children content model to zero or one. In other words, the child
   * is optional.
   * <p>
   * For example:
   * <pre>
   * &lt;!ELEMENT elem (foo?)&gt;
   * </pre>
   *
   * @see #OCCURS_ZERO_OR_MORE
   * @see #OCCURS_ONE_OR_MORE
   */
  public static final short OCCURS_ZERO_OR_ONE = 2;

  /**
   * This occurrence count limits the element, choice, or sequence in a
   * children content model to zero or more. In other words, the child
   * may appear an arbitrary number of times, or not at all. This
   * occurrence count is also used for mixed content models.
   * <p>
   * For example:
   * <pre>
   * &lt;!ELEMENT elem (foo*)&gt;
   * &lt;!ELEMENT elem (#PCDATA|foo|bar)*&gt;
   * </pre>
   *
   * @see #OCCURS_ZERO_OR_ONE
   * @see #OCCURS_ONE_OR_MORE
   */
  public static final short OCCURS_ZERO_OR_MORE = 3;

  /**
   * This occurrence count limits the element, choice, or sequence in a
   * children content model to one or more. In other words, the child
   * may appear an arbitrary number of times, but must appear at least
   * once.
   * <p>
   * For example:
   * <pre>
   * &lt;!ELEMENT elem (foo+)&gt;
   * </pre>
   *
   * @see #OCCURS_ZERO_OR_ONE
   * @see #OCCURS_ZERO_OR_MORE
   */
  public static final short OCCURS_ONE_OR_MORE = 4;

  //
  // XMLDTDContentModelHandler methods
  //

  /**
   * The start of a content model. Depending on the type of the content
   * model, specific methods may be called between the call to the
   * startContentModel method and the call to the endContentModel method.
   *
   * @param elementName The name of the element.
   * @param augmentations Additional information that may include infoset augmentations.
   * @throws XNIException Thrown by handler to signal an error.
   */
  public void startContentModel(String elementName, Augmentations augmentations)
      throws XNIException;

  /**
   * A content model of ANY.
   *
   * @param augmentations Additional information that may include infoset augmentations.
   * @throws XNIException Thrown by handler to signal an error.
   * @see #empty
   * @see #startGroup
   */
  public void any(Augmentations augmentations) throws XNIException;

  /**
   * A content model of EMPTY.
   *
   * @param augmentations Additional information that may include infoset augmentations.
   * @throws XNIException Thrown by handler to signal an error.
   * @see #any
   * @see #startGroup
   */
  public void empty(Augmentations augmentations) throws XNIException;

  /**
   * A start of either a mixed or children content model. A mixed
   * content model will immediately be followed by a call to the
   * <code>pcdata()</code> method. A children content model will
   * contain additional groups and/or elements.
   *
   * @param augmentations Additional information that may include infoset augmentations.
   * @throws XNIException Thrown by handler to signal an error.
   * @see #any
   * @see #empty
   */
  public void startGroup(Augmentations augmentations) throws XNIException;

  /**
   * The appearance of "#PCDATA" within a group signifying a
   * mixed content model. This method will be the first called
   * following the content model's <code>startGroup()</code>.
   *
   * @param augmentations Additional information that may include infoset augmentations.
   * @throws XNIException Thrown by handler to signal an error.
   * @see #startGroup
   */
  public void pcdata(Augmentations augmentations) throws XNIException;

  /**
   * A referenced element in a mixed or children content model.
   *
   * @param elementName The name of the referenced element.
   * @param augmentations Additional information that may include infoset augmentations.
   * @throws XNIException Thrown by handler to signal an error.
   */
  public void element(String elementName, Augmentations augmentations)
      throws XNIException;

  /**
   * The separator between choices or sequences of a mixed or children
   * content model.
   *
   * @param separator The type of children separator.
   * @param augmentations Additional information that may include infoset augmentations.
   * @throws XNIException Thrown by handler to signal an error.
   * @see #SEPARATOR_CHOICE
   * @see #SEPARATOR_SEQUENCE
   */
  public void separator(short separator, Augmentations augmentations)
      throws XNIException;

  /**
   * The occurrence count for a child in a children content model or
   * for the mixed content model group.
   *
   * @param occurrence The occurrence count for the last element or group.
   * @param augmentations Additional information that may include infoset augmentations.
   * @throws XNIException Thrown by handler to signal an error.
   * @see #OCCURS_ZERO_OR_ONE
   * @see #OCCURS_ZERO_OR_MORE
   * @see #OCCURS_ONE_OR_MORE
   */
  public void occurrence(short occurrence, Augmentations augmentations)
      throws XNIException;

  /**
   * The end of a group for mixed or children content models.
   *
   * @param augmentations Additional information that may include infoset augmentations.
   * @throws XNIException Thrown by handler to signal an error.
   */
  public void endGroup(Augmentations augmentations) throws XNIException;

  /**
   * The end of a content model.
   *
   * @param augmentations Additional information that may include infoset augmentations.
   * @throws XNIException Thrown by handler to signal an error.
   */
  public void endContentModel(Augmentations augmentations) throws XNIException;

  // set content model source
  public void setDTDContentModelSource(XMLDTDContentModelSource source);

  // get content model source
  public XMLDTDContentModelSource getDTDContentModelSource();

} // interface XMLDTDContentModelHandler
